documents, he never says i need you to go to my dorm room, get the backpack and take it away. there's an implied invitation, come to my room and take anything umt. it also says they consider it a joke. then they go to the room and find the backpack. that's when, according to the fbi, says one of them knew, at that point, is the term the fbi uses, knew that tsarnaev was involved in the bombing. you heard the lawyer for one of the defendants who says no. he says no, they did not think they were taking evidence directly related to the bombing out of the dorm room. why they were taking it out, he doesn't say. >> james cavanagh, you have worked investigations like this. you came across this package of evidence, the texts and then the knowledge that these people went to the dorm room, what they did, the roommate tells you this is what they did with that stuff.